Extract ParameterFilter class from FilterParameters mixin

Signed-off-by: wycats <wycats@gmail.com>

1 files changed, 72 insertions, 0 deletions

diff --git a/actionpack/lib/action_dispatch/http/parameter_filter.rb b/actionpack/lib/action_dispatch/http/parameter_filter.rb
new file mode 100644
index 0000000000..1480e8f77c
--- /dev/null
+++ b/actionpack/lib/action_dispatch/http/parameter_filter.rb
@@ -0,0 +1,72 @@
+module ActionDispatch
+  module Http
+    class ParameterFilter
+
+      def initialize(filters)
+        @filters = filters
+      end
+
+      def filter(params)
+        if enabled?
+          compiled_filter.call(params)
+        else
+          params.dup
+        end
+      end
+
+    private
+
+      def enabled?
+        @filters.present?
+      end
+
+      def compiled_filter
+        @compiled_filter ||= begin
+          regexps, blocks = compile_filter
+
+          lambda do |original_params|
+            filtered_params = {}
+
+            original_params.each do |key, value|
+              if regexps.find { |r| key =~ r }
+                value = '[FILTERED]'
+              elsif value.is_a?(Hash)
+                value = filter(value)
+              elsif value.is_a?(Array)
+                value = value.map { |v| v.is_a?(Hash) ? filter(v) : v }
+              elsif blocks.present?
+                key = key.dup
+                value = value.dup if value.duplicable?
+                blocks.each { |b| b.call(key, value) }
+              end
+
+              filtered_params[key] = value
+            end
+
+            filtered_params
+          end
+        end
+      end
+
+      def compile_filter
+        strings, regexps, blocks = [], [], []
+
+        @filters.each do |item|
+          case item
+          when NilClass
+          when Proc
+            blocks << item
+          when Regexp
+            regexps << item
+          else
+            strings << item.to_s
+          end
+        end
+
+        regexps << Regexp.new(strings.join('|'), true) unless strings.empty?
+        [regexps, blocks]
+      end
+
+    end
+  end
+end